Winchester disc drives are being used in computers to store increasingly large amounts of information; their long term reliability as well as cost of production in an age of reduced prices for personal computers is critical. The typical Winchester disc drive is a system with a limited number of mechanical parts, including a spindle motor which mounts one or more discs for constant speed rotation, and an actuator carrying a transducer at one end and a voice coil motor at the other and operable in response to commands to the voice coil motor to position the transducer over a selected track to read and write data.
As one of the most expensive elements of a disc drive, as well as one of the largest and most mechanically complex, many design efforts are intended to minimize the cost and ease of assembly of the spindle motor. This particular invention is especially directed to improving a spindle motor design which incorporates a central connector which extends through the bottom of the shaft and into and through the base of the disc drive, so that external connections can easily be made from below the motor to a control board attached to the housing which will supply energizing current to the disc drive spindle motor. It is apparent that it is essential to provide a reliable connector from the source of external power to the stator of the spindle motor so that the motor can be reliably energized. Over time, the disc drive and the motor which runs at constant speed for hours at a time can be subjected to shock and continuing vibration; this could easily cause connections to loosen or a plug which inserts the connections into the base of the motor to even become lose and slip out of the motor, causing the disc drive to lose power. Any slippage or deterioration in the quality of the plug connector could cause such a loss of power. Therefore, an improved connector which can fit into the hollow center of a shaft and which will provide a long lifetime without deterioration of the electrical contacts is highly desirable.